Scanning display module and temperature self-feedback method

Abstract

Disclosed in the present invention are a scanning display module and a temperature self-feedback method. The scanning display module comprises: a housing; a piezoelectric actuator, fixed inside the housing by means of a support structure; a thermostatic element, arranged inside the housing; and a temperature compensation controller, configured to extract an electrical signal in a drive circuit of the piezoelectric actuator as a feedback signal, and to adjust the thermostatic element on the basis of the feedback signal so as to perform temperature compensation on the piezoelectric actuator. In the solution, no external sensor is required, and the thermostatic element is adjusted only by means of the feedback signal extracted from the drive circuit to perform temperature compensation. Under large variations in ambient temperature, precise temperature compensation for the piezoelectric actuator is achieved, so that the response characteristics of the piezoelectric actuator remain unchanged, and a scanning trajectory remains stable.

Description

A scanning display module and a temperature self-feedback method

[0001] This application claims priority to the following invention applications filed on June 27, 2024, with application number "202410845119.2" and patent title "A Scanning Display Module and Temperature Self-Feedback Method"; the following invention applications filed on June 27, 2024, with application number "202410845014.7" and patent title "A Scanning Display Module"; and the entire contents of the following invention applications filed on June 27, 2024, with application number "202410845008.1" and patent title "A Piezoelectric Scanning Device and Scanning Display Module" are incorporated herein by reference. Technical Field

[0002] This application relates to the field of projection display, and more particularly to a scanning display module and a temperature self-feedback method. Background Technology

[0003] The imaging principle of fiber scanning display (FSD) technology is that an actuator drives an optical fiber to move along a predetermined two-dimensional scanning trajectory, and modulates the light output of the light corresponding to each pixel of the image to be displayed. Then, the light corresponding to each pixel of the image to be displayed is projected onto the projection surface one by one through the optical fiber to form a projected image.

[0004] In FSD applications, actuators are typically made of piezoelectric devices and have a generally complex structure, resulting in complex frequency characteristics. When the temperature changes, the characteristics of the piezoelectric actuator change nonlinearly, which can cause changes in the projected image and affect the image quality. Summary of the Invention

[0005] The purpose of this invention is to provide a scanning display module and a temperature self-feedback method to alleviate the technical problem in the prior art where the characteristics of the piezoelectric actuator change non-linearly when the temperature changes, which leads to changes in the projected image and affects the imaging quality.

[0006] To achieve the above-mentioned objective, a first aspect of the present invention provides a scanning display module, comprising:

[0007] case;

[0008] A piezoelectric actuator, wherein the piezoelectric actuator is fixed inside the housing by a support structure;

[0009] The temperature control element is disposed inside the housing;

[0010] A temperature compensation controller is used to extract the electrical signal in the drive circuit of the piezoelectric actuator as a feedback signal, and adjust the constant temperature element based on the feedback signal to compensate the temperature of the piezoelectric actuator.

[0011] Optionally, the electrical signal in the drive circuit includes a current signal flowing through the piezoelectric actuator.

[0012] Optionally, the electrical signals in the drive circuit include the voltage signals across the piezoelectric actuator.

[0013] Optionally, the temperature-regulating element is a TEC semiconductor device.

[0014] Optionally, the temperature-regulating element is a heating element, which is used to maintain the operating temperature of the piezoelectric actuator above the maximum rated operating ambient temperature of the scanning display module.

[0015] Optionally, the heating element is made of positive temperature coefficient (PTC) material.

[0016] Optionally, the heating element includes a coating applied to the surface of the piezoelectric actuator.

[0017] Optionally, a heat insulation layer is provided on the outer surface of the housing.

[0018] Optionally, the inner surface of the housing is mirrored.

[0019] Optionally, after extracting the feedback signal, the temperature compensation controller calculates the difference between the feedback signal and the initial value of the signal, and adjusts the constant temperature element based on the difference until the difference meets a preset condition.

[0020] A second aspect of this invention provides a temperature self-feedback method applied in a scanning display module, the method comprising:

[0021] The electrical signal in the drive circuit of the piezoelectric actuator in the scanning display module is extracted as a feedback signal;

[0022] The temperature control element installed in the scanning display module is adjusted based on the feedback signal to compensate the temperature of the piezoelectric actuator.

[0023] A third aspect of the present invention provides a scanning display module, comprising:

[0024] case;

[0025] A piezoelectric actuator, wherein the piezoelectric actuator is fixed inside the housing by a support structure;

[0026] A heating element is disposed inside the housing, and the heating element is used to maintain the operating temperature of the piezoelectric actuator above the ambient temperature of the scanning display module.

[0027] Optionally, the scanning display module includes a temperature compensation controller, used to extract the electrical signal in the drive circuit of the piezoelectric actuator as a feedback signal, and adjust the heating element based on the feedback signal to compensate the temperature of the piezoelectric actuator.

[0028] Optionally, the electrical signal in the drive circuit includes a current signal flowing through the piezoelectric actuator.

[0029] Optionally, the electrical signals in the drive circuit include the voltage signals across the piezoelectric actuator.

[0030] Optionally, the scanning display module includes a temperature compensation controller for acquiring the ambient temperature of the scanning display module and adjusting the heating element so that the operating temperature of the piezoelectric actuator is higher than the ambient temperature.

[0031] Optionally, the heating element is made of positive temperature coefficient (PTC) material.

[0032] Optionally, the driving voltage of the heating element is limited to a set amplitude.

[0033] Optionally, the heating element includes a coating applied to the surface of the piezoelectric actuator.

[0034] Optionally, the heating element is disposed around the piezoelectric actuator.

[0035] Optionally, the heating element is fixed to the inner wall of the housing by a support structure.

[0036] A fourth aspect of the present invention provides a piezoelectric scanning device, comprising:

[0037] piezoelectric actuator;

[0038] A temperature-controlled element is disposed on the surface of the piezoelectric actuator, and the temperature-controlled element is used to perform temperature compensation on the piezoelectric actuator during the scanning process of the piezoelectric actuator.

[0039] Optionally, the piezoelectric actuator has a sheet-like structure, and the thermostatic element is disposed on the upper and / or lower surface of the piezoelectric actuator.

[0040] Optionally, the temperature-regulating element is a TEC semiconductor device.

[0041] Optionally, the thermostatic element is a heating element.

[0042] Optionally, the heating element is made of positive temperature coefficient (PTC) material.

[0043] Optionally, the PTC material is applied to the surface of the piezoelectric actuator by coating.

[0044] A fifth aspect of the present invention provides a scanning display module, comprising:

[0045] The housing and the piezoelectric scanning device as described in the fourth aspect; the piezoelectric actuator is fixed inside the housing by a support structure.

[0046] Optionally, the housing is a vacuum-sealed structure.

[0047] Optionally, a heat insulation layer is provided on the outer surface of the housing.

[0048] Optionally, the inner surface of the housing is mirrored.

[0049] One or more technical solutions in the embodiments of the present invention have at least the following technical effects or advantages:

[0050] In this embodiment of the invention, a temperature compensation controller extracts the electrical signal from the drive circuit of the piezoelectric actuator as a feedback signal, and adjusts the thermostatic element based on the feedback signal to compensate for the temperature of the piezoelectric actuator. This achieves temperature compensation without the need for external sensors, relying solely on the feedback signal extracted from the drive circuit to adjust the thermostatic element. The piezoelectric actuator achieves precise temperature compensation even with wide-range ambient temperature changes, maintaining its response characteristics and stabilizing the scanning trajectory. This alleviates the technical problem in the prior art where the non-linear changes in piezoelectric actuator characteristics during temperature variations lead to changes in the projected image and affect imaging quality. By implementing temperature compensation for the piezoelectric actuator with a few components, system complexity is reduced, circuit structure, area, and cost are simplified, while simultaneously improving system reliability and real-time performance. Attached Figure Description

[0051] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort:

[0052] Figure 1 is a system block diagram of the scanning display module provided in an embodiment of the present invention;

[0053] Figure 2 is a schematic diagram of the drive circuit of the piezoelectric actuator provided in an embodiment of the present invention;

[0054] Figure 3 is a schematic diagram of the scanning display module provided in an embodiment of the present invention;

[0055] Figure 4 is a schematic flowchart of the temperature self-feedback method provided in an embodiment of the present invention;

[0056] Figure 5 is another structural schematic diagram of the scanning display module provided in an embodiment of the present invention;

[0057] Figure 6 is another system block diagram of the scanning display module provided in an embodiment of the present invention;

[0058] Figure 7 is another structural schematic diagram of the scanning display module provided in an embodiment of the present invention;

[0059] Figure 8 is a schematic diagram of the piezoelectric scanning device provided in an embodiment of the present invention;

[0060] Figure 9 is another system block diagram of the scanning display module provided in an embodiment of the present invention. Detailed Implementation

[0061] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0062] In this embodiment of the invention, an actuator and an optical fiber constitute a fiber optic scanning device (also referred to as a fiber optic scanner, scanning device, scanner, or piezoelectric scanning device). Since the actuator is primarily composed of piezoelectric ceramic PZT, the scanner's response characteristics change with variations in environmental conditions such as temperature. The purpose of this invention is to compensate for these changes in actuator response characteristics caused by variations in external conditions such as temperature. In practical applications, other piezoelectric materials can also be used for the actuator, and this invention does not impose any limitations on this. In this embodiment of the invention, the actuator can also be referred to as a piezoelectric actuator, a fiber optic scanning actuator, etc. The different descriptions used above for fiber optic scanning devices and actuators should not be construed as limitations on this invention.

[0063] For schemes using drive signal compensation, complex calibration and other measures are required to determine the actuator's temperature-dependent characteristics before compensation is performed via the drive signal. Schemes using vibration trajectory detection for compensation generally have high system complexity and are not suitable for mass production, leading to high system manufacturing costs. General temperature control schemes encounter problems such as the inability to place temperature sensors at the actuator's vibration location, delays in heat transfer, and the inability to reflect the actuator's true state in real time. Furthermore, fiber optic scanning devices are highly sensitive to temperature during high-frequency vibration, requiring very high temperature detection accuracy and placing high demands on the detection circuitry, thus increasing circuit area and cost.

[0064] As shown in Figure 1, the scanning display module includes a housing 10, a piezoelectric actuator 11 which can be fixed inside the housing 10 by a support structure, a drive circuit 12 for providing a drive signal to the piezoelectric actuator 11, a thermostatic element 13 disposed inside the housing 10, and a temperature compensation controller 14 for extracting the electrical signal from the drive circuit 12 of the piezoelectric actuator 11 as a feedback signal and adjusting the thermostatic element 13 based on the feedback signal to compensate the temperature of the piezoelectric actuator 11.

[0065] In this embodiment of the invention, the temperature characteristics of the piezoelectric actuator 11 are utilized to extract the electrical signals (voltage signals / current signals) at both ends of the piezoelectric actuator 11 after temperature drift as feedback signals to adjust the constant temperature element 13, so as to compensate the temperature of the piezoelectric actuator 11.

[0066] The temperature compensation controller 14 extracts the electrical signal from the drive circuit 12 of the piezoelectric actuator 11 as a feedback signal, and adjusts the thermostatic element 13 based on the feedback signal to compensate for the temperature of the piezoelectric actuator 11, thus maintaining the response characteristics of the piezoelectric actuator 11 and stabilizing the scanning trajectory. Using this scheme, temperature compensation of the piezoelectric actuator 11 is achieved with a few components, reducing system complexity, simplifying circuit structure, area, and cost, while improving system reliability and real-time performance.

[0067] In this embodiment of the invention, the constant temperature element 13 can use a TEC semiconductor device to simultaneously achieve cooling and heating. In order to simplify the structure and reduce the size, materials such as PTC (Positive Temperature Coefficient) can also be used to achieve the heating function, maintaining the operating temperature of the piezoelectric actuator 11 above the product's maximum rated operating ambient temperature, i.e., Tfsd = Tmax + dT, where Tfsd is the internal temperature of the device, Tmax is the maximum rated operating ambient temperature of the device, and the value of dT can be selected according to actual needs. By maintaining Tfsd above the operating ambient temperature, the influence of ambient temperature changes on the characteristics of the piezoelectric actuator 11 can be eliminated, thereby ensuring the performance stability of the piezoelectric actuator 11.

[0068] In this embodiment of the invention, when extracting the electrical signal in the driving circuit 12 of the piezoelectric actuator 11, the voltage signal or current signal of the piezoelectric ceramic can be extracted as a feedback signal depending on the different driving methods of the piezoelectric ceramic.

[0069] In one possible implementation, as shown in Figure 2, when using LC driving, the free-end voltage waveform of the piezoelectric actuator 11 can be used as the feedback signal. The voltage signal at the FB terminal can also be used as the feedback signal. Since the amplitude and phase of the voltage signal at FB will change after the piezoelectric ceramic experiences temperature drift, both the amplitude and phase of the voltage signal can be used as feedback signals. Furthermore, since the amplitude detection circuit is simpler in structure than the phase detection circuit, the amplitude signal can be selected as the feedback error signal.

[0070] In another possible implementation, the current of the piezoelectric ceramic can also be used as the feedback signal. Similarly, the amplitude of the current signal can be selected as the feedback error signal. In specific implementation, the current signal can be acquired by connecting a sampling resistor in series at the grounding terminal of the piezoelectric ceramic.

[0071] In this embodiment of the invention, the thermostatic element 13 can be either a heating element or a cooling element. For the heating element, a positive temperature coefficient (PTC) material can be used. In specific implementation, combined with PTC drive voltage limiting, overheating and spontaneous combustion can be effectively prevented after runaway. To ensure heat transfer efficiency and response speed, the heating element can be placed inside the encapsulation housing 10, or a polymer PTC material can be used as a coating and directly coated on the actuator surface.

[0072] In this embodiment of the invention, the housing 10 can adopt an encapsulated heat-insulating structure, as shown in Figure 3. The piezoelectric actuator 11 is fixed inside the housing 10 by a low thermal conductivity support structure 15. The housing 10 is sealed by a vacuum 18, and the inner wall 16 of the housing can be processed into a mirror surface. A thermostatic element 13 is provided on the piezoelectric actuator 11, which can be a PTC heating layer or other cooling element. A heat insulation layer 17 is provided on the outer layer of the housing 10. In specific implementations, a material with low thermal conductivity can be used as the heat insulation layer 17. In other embodiments, the thermostatic element 13 may not be provided on the piezoelectric actuator 11, but can be provided inside the housing 10. The thermostatic element 13 can be provided around the piezoelectric actuator 11 or in other positions inside the housing 10. Those skilled in the art can set it according to actual needs, and the present invention does not limit this.

[0073] In this embodiment of the invention, the scanning display device can increase the internal and external thermal resistance of the device, reduce the internal temperature sensitivity of the device to the external environment, reduce the external heat dissipation power, and reduce the heating power consumption of the device by means of vacuum encapsulation, reflection of the inner wall 16, and heat insulation material in the shell 10.

[0074] In this embodiment of the invention, a PID controller can be used as the temperature compensation controller. After the image output by the fiber optic scanning device is correctly initialized, the feedback signal value is extracted and recorded as the initial signal value S0, which is used as the preset value for the PID controller. During the operation of the piezoelectric actuator, the feedback signal St is acquired in real time. The error input value of the PID controller is set to Error = St - S0. In specific implementation, a better control effect can be obtained by adjusting the PID parameters. The preset condition corresponding to the difference value Error can be set near 0, thereby achieving real-time and precise temperature compensation.

[0075] In this embodiment of the invention, additional limiting protection measures can be added to prevent the device from overheating in the event of a runaway. For example, measures such as limiting the maximum power and maximum temperature of the heating element can be adopted. When using PTC as the heating material, the risk of overheating in the event of a runaway can be effectively avoided. Furthermore, the internal temperature of the device is set above the maximum rated operating ambient temperature, and the dual measures of the PTC heating material characteristics ensure that there is no risk of overheating and spontaneous combustion in the event of a runaway. In other embodiments, the heating material can also be used in conjunction with a temperature sensor for temperature control, and this invention does not limit this approach.

[0076] In this embodiment of the invention, by employing a built-in temperature regulation mechanism and using the piezoelectric ceramic's own electrical signal as the controller error input, precise temperature control of the PZT actuator can be achieved without adding external sensors or complex circuits. This ensures the performance stability of the piezoelectric actuator over a wide temperature range, significantly improving its reliability and real-time performance. Furthermore, the simplified design in this embodiment reduces costs and improves the overall system efficiency and application flexibility.

[0077] Based on the same inventive concept, this embodiment of the invention also provides a temperature self-feedback method, applied in a scanning display module, as shown in Figure 4. The method includes the following steps.

[0078] Step 401: Extract the electrical signal from the drive circuit of the piezoelectric actuator in the scanning display module as a feedback signal;

[0079] Step 402: Adjust the constant temperature element set in the scanning display module based on the feedback signal to perform temperature compensation for the piezoelectric actuator.

[0080] Regarding the temperature self-feedback method in the above embodiments, the specific methods of each execution operation have been described in detail in the embodiments related to the module, and will not be elaborated here.

[0081] As shown in Figure 5, which is a schematic diagram of the structure of the scanning display module, the scanning display module includes a housing 10; a piezoelectric actuator 11, which can be fixed inside the housing 10 by a support structure; and a heating element 19, which is disposed inside the housing 10. The heating element 19 is used to maintain the operating temperature of the piezoelectric actuator 11 higher than the ambient temperature of the scanning display module.

[0082] In the above scheme, the operating temperature of the piezoelectric actuator 11 is maintained higher than the ambient temperature of the scanning display module by the heating element 19, thereby eliminating the influence of ambient temperature changes on the characteristics of the piezoelectric actuator 11 and ensuring the performance stability of the piezoelectric actuator 11.

[0083] In one possible implementation, the temperature characteristics of the piezoelectric actuator 11 itself can be utilized to extract the electrical signal (voltage signal / current signal) at both ends of the piezoelectric actuator 11 after temperature drift as a feedback signal, and the heating element 19 can be adjusted based on the feedback signal to compensate the temperature of the piezoelectric actuator 11.

[0084] As shown in Figure 6, the scanning display module includes a drive circuit 12 and a temperature compensation controller 14. The temperature compensation controller 14 extracts the electrical signal from the drive circuit 12 as a feedback signal and adjusts the heating element 19 based on this feedback signal to compensate the temperature of the piezoelectric actuator 11, maintaining its response characteristics and stabilizing the scanning trajectory. Using this scheme, temperature compensation of the piezoelectric actuator 11 is achieved with fewer components, reducing system complexity, simplifying circuit structure, area, and cost, while simultaneously improving system reliability and real-time performance.

[0085] In this embodiment of the invention, the heating element 19 can be made of materials such as PTC (Positive Temperature Coefficient) to achieve the heating function, maintaining the operating temperature of the piezoelectric actuator 11 above the product's maximum rated operating ambient temperature, i.e., Tfsd = Tmax + dT, where Tfsd is the internal temperature of the device, Tmax is the ambient temperature of the device, and the value of dT can be selected according to actual needs. By maintaining Tfsd above the operating ambient temperature, the influence of ambient temperature changes on the characteristics of the piezoelectric actuator 11 can be eliminated, thereby ensuring the performance stability of the piezoelectric actuator 11. The ambient temperature can be the product's maximum rated operating ambient temperature, i.e., the highest possible rated temperature of the environment in which it is located.

[0086] In another possible implementation, the temperature compensation controller 14 can be used to obtain the ambient temperature of the scanning display module and adjust the heating element 19 so that the operating temperature of the piezoelectric actuator 11 is higher than the ambient temperature. In specific implementation, the temperature can be controlled by the heating element 19 in conjunction with the temperature sensor.

[0087] In this embodiment of the invention, when extracting the electrical signal in the driving circuit 12 of the piezoelectric actuator 11, the voltage signal or current signal of the piezoelectric ceramic can be extracted as a feedback signal depending on the different driving methods of the piezoelectric ceramic.

[0088] In this embodiment of the invention, the heating element 19 can be made of a positive temperature coefficient PTC material. In specific implementation, combined with PTC drive voltage limiting, the drive voltage is limited to a set range, which can effectively prevent overheating and spontaneous combustion after runaway. To ensure heat transfer efficiency and response speed, the heating element 19 can be disposed inside the encapsulation housing 10, or a polymer PTC material can be used as a coating and directly coated on the surface of the piezoelectric actuator 11.

[0089] In this embodiment of the invention, the housing 10 can adopt an encapsulated heat-insulating structure, as shown in FIG7. The piezoelectric actuator 11 is fixed inside the housing 10 by a support structure 15 with low thermal conductivity. The housing 10 is sealed by vacuum 18, and the inner wall 16 of the housing can be processed into a mirror surface. A heating element 19 is provided on the piezoelectric actuator 11, and the heating element 19 can be a PTC heating layer. A heat insulation layer 17 is provided on the outer layer of the housing 10. In specific implementation, a material with low thermal conductivity can be used as the heat insulation layer 17. In other embodiments, the heating element 19 may not be provided on the piezoelectric actuator 11, but can be provided inside the housing 10. The heating element 19 can be provided around the piezoelectric actuator 11, or it can be provided in other positions inside the housing 10, for example, fixed to the inner wall 16 of the housing by a support structure. Those skilled in the art can set it according to actual needs, and the present invention does not limit it.

[0090] As shown in FIG8, the piezoelectric scanning device includes a piezoelectric actuator 11 and a thermostatic element 13. The thermostatic element 13 is disposed on the surface of the piezoelectric actuator 11 and is used to perform temperature compensation on the piezoelectric actuator 11 during the scanning process.

[0091] In the above scheme, the operating temperature of the piezoelectric actuator 11 is kept stable by the constant temperature element 13, thereby eliminating the influence of ambient temperature changes on the characteristics of the piezoelectric actuator 11 and ensuring the performance stability of the piezoelectric actuator 11.

[0092] In this embodiment of the invention, the arrangement of the thermostatic element 13 can be selected according to the different structures of the piezoelectric scanning device. For example, assuming the piezoelectric actuator 11 has a sheet-like structure, the thermostatic element 13 can be disposed on the upper or lower surface of the piezoelectric actuator 11, or simultaneously on both the upper and lower surfaces; while when the piezoelectric actuator 11 has a tubular structure, the thermostatic element 13 can be disposed on the outer or inner surface of the tubular structure, or simultaneously on both the inner and outer surfaces of the tubular structure. This invention does not impose any restrictions on this.

[0093] In this embodiment of the invention, the following control method can be used to perform temperature compensation on the piezoelectric actuator 11.

[0094] Utilizing the temperature characteristics of the piezoelectric actuator 11 itself, the electrical signals (voltage signals / current signals) at both ends of the piezoelectric actuator 11 after temperature drift are extracted as feedback signals, and the temperature control element 13 is adjusted based on the feedback signals to compensate the temperature of the piezoelectric actuator 11.

[0095] When extracting the electrical signal from the drive circuit 12 of the piezoelectric actuator 11, the voltage signal or current signal of the piezoelectric ceramic can be extracted as a feedback signal depending on the different driving methods of the piezoelectric ceramic.

[0096] For example, as shown in Figure 9, the scanning display module includes a drive circuit 12 and a temperature compensation controller 14. As shown in Figure 2, when driven by LC, the free-end voltage waveform of the piezoelectric actuator 11 can be used as the feedback signal. The voltage signal at the FB terminal can also be used as the feedback signal. Since the amplitude and phase of the voltage signal at FB will change after the piezoelectric ceramic experiences temperature drift, both the amplitude and phase of the voltage signal can be used as feedback signals. Furthermore, since the amplitude detection circuit is simpler in structure than the phase detection circuit, the amplitude signal can be selected as the feedback error signal.

[0097] Of course, the current of the piezoelectric ceramic can also be used as the feedback signal. Similarly, the amplitude of the current signal can be selected as the feedback error signal. In the specific implementation process, the current signal can be collected by connecting a sampling resistor in series at the grounding terminal of the piezoelectric ceramic.

[0098] In this embodiment of the invention, the thermostatic element 13 can be either a heating element or a cooling element. For the heating element, a positive temperature coefficient (PTC) material can be used. In specific implementation, combined with PTC drive voltage limiting, overheating and spontaneous combustion can be effectively prevented after runaway. To ensure heat transfer efficiency and response speed, the heating element can be coated with a polymer PTC material directly onto the actuator surface.

[0099] Based on the same inventive concept, this invention also provides a scanning display module. Various specific methods of the scanning display module have been described in detail in the above embodiments related to piezoelectric scanning devices, and will not be elaborated here.

[0100] All features disclosed in this specification, or all steps in all disclosed methods or processes, may be combined in any way, except for mutually exclusive features and / or steps.

[0101] Any feature disclosed in this specification (including any appended claims, abstract, and drawings) may be replaced by other equivalent or similar features, unless specifically stated otherwise. That is, unless specifically stated otherwise, each feature is merely one example of a series of equivalent or similar features.

[0102] This invention is not limited to the specific embodiments described above. The invention extends to any new feature or combination disclosed in this specification, as well as any new method or process step or combination disclosed herein.

Claims

1. A scanning display module, characterized in that, include: case; A piezoelectric actuator, wherein the piezoelectric actuator is fixed inside the housing by a support structure; The temperature control element is disposed inside the housing; A temperature compensation controller is used to extract the electrical signal in the drive circuit of the piezoelectric actuator as a feedback signal, and adjust the constant temperature element based on the feedback signal to compensate the temperature of the piezoelectric actuator.

2. The scanning display module as described in claim 1, characterized in that, The electrical signals in the drive circuit include the current signals flowing through the piezoelectric actuator.

3. The scanning display module as described in claim 1, characterized in that, The electrical signals in the drive circuit include the voltage signals across the piezoelectric actuator.

4. The scanning display module as described in claim 1, characterized in that, The temperature-controlled element is a TEC semiconductor device.

5. The scanning display module as described in claim 1, characterized in that, The constant temperature element is a heating element, which is used to maintain the operating temperature of the piezoelectric actuator above the maximum rated operating ambient temperature of the scanning display module.

6. The scanning display module as described in claim 5, characterized in that, The heating element is made of positive temperature coefficient (PTC) material.

7. The scanning display module as described in claim 6, characterized in that, The heating element includes a coating applied to the surface of the piezoelectric actuator.

8. The scanning display module as described in claim 1, characterized in that, A heat insulation layer is provided on the outer surface of the shell.

9. The scanning display module as described in claim 1, characterized in that, The inner surface of the housing is mirrored.

10. The scanning display module as described in claim 1, characterized in that, After extracting the feedback signal, the temperature compensation controller calculates the difference between the feedback signal and the initial value of the signal, and adjusts the constant temperature element based on the difference until the difference meets a preset condition.

11. A temperature self-feedback method, applied in a scanning display module, characterized in that, The method includes: The electrical signal in the drive circuit of the piezoelectric actuator in the scanning display module is extracted as a feedback signal; The temperature control element installed in the scanning display module is adjusted based on the feedback signal to compensate the temperature of the piezoelectric actuator.

12. A scanning display module, characterized in that, include: case; A piezoelectric actuator, wherein the piezoelectric actuator is fixed inside the housing by a support structure; A heating element is disposed inside the housing, and the heating element is used to maintain the operating temperature of the piezoelectric actuator above the ambient temperature of the scanning display module.

13. The scanning display module as described in claim 12, characterized in that, The scanning display module includes a temperature compensation controller, which is used to extract the electrical signal in the drive circuit of the piezoelectric actuator as a feedback signal, and adjust the heating element based on the feedback signal to compensate the temperature of the piezoelectric actuator.

14. The scanning display module as described in claim 13, characterized in that, The electrical signals in the drive circuit include the current signals flowing through the piezoelectric actuator.

15. The scanning display module as described in claim 13, characterized in that, The electrical signals in the drive circuit include the voltage signals across the piezoelectric actuator.

16. The scanning display module as described in claim 12, characterized in that, The scanning display module includes a temperature compensation controller for acquiring the ambient temperature of the scanning display module and adjusting the heating element so that the operating temperature of the piezoelectric actuator is higher than the ambient temperature.

17. The scanning display module as described in claim 12, characterized in that, The heating element is made of positive temperature coefficient (PTC) material.

18. The scanning display module as described in claim 17, characterized in that, The heating element includes a coating applied to the surface of the piezoelectric actuator.

19. The scanning display module as described in claim 12, characterized in that, The driving voltage of the heating element is limited to a set amplitude.

20. The scanning display module as described in claim 12, characterized in that, The heating element is disposed around the piezoelectric actuator.

21. The scanning display module as described in claim 12, characterized in that, The heating element is fixed to the inner wall of the housing by a support structure.

22. A piezoelectric scanning device, characterized in that, include: piezoelectric actuator; A temperature-controlled element is disposed on the surface of the piezoelectric actuator, and the temperature-controlled element is used to perform temperature compensation on the piezoelectric actuator during the scanning process of the piezoelectric actuator.

23. The piezoelectric scanning device as described in claim 22, characterized in that, The piezoelectric actuator has a sheet-like structure, and the thermostatic element is disposed on the upper and / or lower surface of the piezoelectric actuator.

24. The piezoelectric scanning device as claimed in claim 22, characterized in that, The temperature-controlled element is a TEC semiconductor device.

25. The piezoelectric scanning device as described in claim 22, characterized in that, The thermostatic element is a heating element.

26. The piezoelectric scanning device as described in claim 25, characterized in that, The heating element is made of positive temperature coefficient (PTC) material.

27. The piezoelectric scanning device as claimed in claim 26, characterized in that, The PTC material is applied to the surface of the piezoelectric actuator by coating.

28. A scanning display module, characterized in that, include: The housing and the piezoelectric scanning device according to any one of claims 22-27; the piezoelectric actuator is fixed inside the housing by a support structure.

29. The scanning display module as described in claim 28, characterized in that, The housing is a vacuum-sealed structure.

30. The scanning display module as described in claim 28, characterized in that, A heat insulation layer is provided on the outer surface of the shell.

31. The scanning display module as described in claim 28, characterized in that, The inner surface of the housing is mirrored.

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